Raid Pillars

[TooNasty]

I have two questions:

Are raid pillars use-able in arena?

If so, would it be possible to macro dropping a pillar when
I launch a trap in one action?

[Deleted]

You mean the raid target flares?
If so, not sure about arenas, but we can't target raid flares (actually, any spell that targets ground) without keyboard interaction - and we can't target two spells at a time.